Single dumbest reason WoW is dying I've ever seen in a signature. "They killed Arthas."

And as a bonus, here's one thing that didn't kill WoW. Lupus.

"Oh, who does my hair? You might have heard of my stylist. It's called the Void!"
"No matter how much you plead I will not sprout tentacles or turn into a giant eyeball. Well, I might. But not because you asked!"